The UN's torture watchdog has criticised the Vatican for its reported refusal to provide information to authorities, including a NSW inquiry into child sex abuse.

The committee in Geneva says it is concerned about allegations that last year the Vatican's representative in Australia invoked diplomatic immunity when refusing to provide documents to assist the NSW Special Commission of Inquiry into sex abuse.

The UN Committee against Torture has called on the Vatican to cooperate promptly with civil authorities.

The UN also criticises the church for its insistence that its obligations under international law stop at the borders of the Holy See.

Prior to the report's publication, the Vatican released a statement saying the committee would heavily criticise its handling of abuse cases but would not find it in violation of an anti-torture convention.

"The Committee did not find the Holy See in violation of the CAT (Convention Against Torture)," the statement said.

The Vatican also said the report did not find the Church's opposition to abortion constituted torture "thus safeguarding the fundamental right of freedom of religion and the protection and promotion of human life".

It was the first time the Vatican had been scrutinised since it signed up in 2002 to a global convention banning cruel, inhuman and degrading treatment and punishment.

It is the second UN committee to have issued a critical report about the Vatican.

Earlier this year the committee on the Rights of the Child said the Church has failed to acknowledged or properly address child sexual abuse.